Windshield wiper blade



Jim 9, 1940. v. H. cHRls'rEN 2,186,193

I WINDSHIELD WIPER BLADE Filed Feb. 8. 1956 :j INVENTOSi 47 ATTORNEYS.

Patented `Ian. 9, 1940 e --UNITEDSTATES mii-:Nr,form-cs l, wINDsHiELD WIPERBLAD.:

' vicini-'11. christen, Dardenne., v' Appiiationrebruary aieseserialpagane@ f 5 Claims. (-o1.15;245).v

i The presentninvention relates to blades for .windshield w iper. mechanisms.-` y

tion are to provide Objects of the present inve a wiper `element,comprising a relatively thin,

5 flexible wipingfstrip. formed of rubber or -its equivalent, having stiffening elementimbedded therein; to provide a wiperelement of shouldered formation embodying a relatively vthin wiping portion and a relatively thick backing portion l adapted to be secured'withinl a channel or other backing member, and including a stiifening elev ment imbedded therein. t o ,stiifen and support the relatively thin wiping portion of the strip to provide such a wiper element in which the stifening h'v` member is flexible to thereby permit limited ilexing of the elem-enti to provid'ea wiper element as just stated in which the forward edge of the stiffening element extends inproximity to the wiping edge of the wiper element,;thus providing uniform .2o flexibility of saidy wiper element over Y its width; and to providea shouldered wiperelement, as

above s tatedi-n -whi ch the stiifening element eX- tends from a point adjacent the wiping edge into the enlarged backing portion of the element.

es Further objects Vofthe present invention are to provide a wiper assembly;y including a supporting channel or correspondingv backing member to which .a flexible rubber wiping strip is secured in outwardly projecting relation, and embodying a :fsstiffeningelement imbedded within the wiper lstrip to strengthen and support the same, thel srtiffening element vbeing positioned within the wiperstrip portion .which projects beyond the supporting channel; lto provide such an assembly :55 in'which the wiper strip is shouldered, having van enlarged Ibacking portion received within the channel and projecting therefrom and having a relatively narrow wiping portionand embodying a stiieningmember imbedded within the wiping y portion and extending intok the shouldered portion; to providesuchan assembly in which the 'stiieningmernber terminates in that portion of the shouldered portion which projects beyond the channel; to provide such an vassemblyv in .a which the shouldered portion is adapted .to `eX relative to the channel and in which'the stillening member extendsintosuch flexing portion of the shouldered part.

Further objects of thepresent invention are to provide a wiperl element comprising `a flexible wiping strip havinga wiping edge and a'proj ectionv'y formed at each side thereof,A in spaced relation .tothe edge; to provide such a wiper element in which the projections are so formed that, in oper- 5 ation, rthe angle between the faces thereof and the glass `'or lothersurface in advance lthereof exceeds 90 degrees,.'so thatthe projections act to lift or shovel'anydirt'riistor other matter from such'glassor other'surface. Y

Further objects and advantagesof the present 5 invention appear inthe following description and in the appendedclaix'ns.

`Inits broader aspects.. the present invention relates generally to the vprovision of Y ilexible wiping elements or squeegees'V suitable for cleaning pur- 10 pesesi kIn its narrow asjgiects, the present invention provides an improved squeegee construction particularly adapted for use inv windshield wipv ing'rnechanis'ms f orfvehicl'es, such'as automobiles.

The. latter constructionslconventionally` include .a baeking' member'lon channel, within which a flexiblel rubber or equivalent wiping strip, formed of one or more la'rnination's,r is secured,'with the `wiping edge thereofprojecting asubstantial dis- `tance beyond the r'riarginaledges of the channel. 20 The channelinember isconventionally reciprois relied upon to provide all ofthe trailing action.

In other( instances, .the 7trailing relation provided by the flexibility of ythe strip is supplemented by providing a loose or sloppyconnection between the strip and the actuating mechanism, such, for

' example, -as byvloo'selyconnecting the channel to the actuating arm, sothat the channel may'flop relative thereto. IIn operation', it will beseen that the principal wiping -action,.due to the trail- 40 ing relation of the'zfstrp relative 'to the arm, is

eiected 'the leading marginal edge of the wiper strip, the trailingmarginal edge thereof being usually v spaced away from vthe glass because the strip meets the glass at an angle other than degrees. f

` In order'tof maintain thejust mentioned edge to surface Contact. ithas been lthe generalpractice lheretoforel tofom thestrip of relatively thick stock with 'a View to, overcoming vthe ,tendency of l5o the strip to flextolsuoh an extent that a substantial".port ion ofthe leading face thereof engagesthe surface to be cleaned, instead of merely the-leading marginal edge thereof. The thicker Y strips are objectionable, however;fora number 5d of reasons; for example, as theywear, and the marginal edgesbecome dulled, the original knife edge contact is lost, and a surface of substantial width is presented to the glass or other surface being cleaned, thereby substantially reducing the effectiveness of the wiper. l

In certain aspects, therefore, the present invention is directed principally to the problem of providing a wiper strip whichl may be constructed in a relatively thin section without introducing the objectionable characteristics above noted. In the illustrated construction, this is accomplished by imbedding a stiffening element within the wiper strip. The stiffening element thus forms a core which supports the material of which the strip is made and strengthens it, and permits the use of an extremely thin strip. By forming, the stiffening member of flexible material, the strip as a whole is permitted to flex a limited amount, and in this respect performs in a manner similar to the conventional relatively thick wiping strip, the wiping being effected by the leading marginal edge. Depending upon the stiffness of the wiper strip, the unit` may be more or less flexible than the strips heretofore used. In the practice of the present invention, it has been found possible to utilize wiping strips having thicknesses ranging from one-quarter to onehalf the thickness ofthe strips commonly used heretofore. A substantial advantage resulting is that, even after substantial periods of wear, in the course of which thev edges may become worn, the very thin strip still presents substantially a knife edge to the glass. v

A further advantage resulting from the stiffener or core is that the flexibility of the wiper remains substantially uniform over the life thereof, the stiffener being substantially unaffected by such wear, as distinguished from the tendency of the prior rubber strips to vary greatly in flexibility, due tohardening of the rubber and other causes.

In further accordance with the present invention, means are provided to act upon the glass or otherl surface to be cleaned, in advance of the above mentioned wiping edge, to leffect a preliminary clearing away of any frost, water or other matter which may have collected thereon. With this arrangement, the previously described wiping edge acts to effect' a final cleaning orv clearing action, or, ina sense, acts to complete or refine the preliminary cleaning action effected by the just mentioned acting means.

, In the specific form illustrated the initially acting means constitutes projections formed at each side of the wiping portion of the blade and y spaced back somewhat from the wiping edge thereof. In operation, due to the flexing of the wiper blade as previously described, the projection on the leading or forward face of the blade is brought into engagementy with the glass or other surface to be cleaned, the other orr trailing projection being held in spaced relation from .in advance thereof exceeds 90 degrees.

the glass. Thus the glass or other surface is engaged along two contact lines, one contact line being afforded by the previously described wiping edge and the other contact line, in advance or other foreign matter from the glass or surface. This shoveling action is advantageous in many respects, particular advantages being that it overcomes to a substantial extent the tendency of the wiperelement to ride over the top of the matter collected on the glass or other surface to be cleaned, and second in that it reduces the tendency heretofore found in multiple blade wipers for the matter being cleaned from the glass or other surface to collect between the respective blades of the wiper.

Further features and advantages of the present invention appear in the following detailed description of an illustrative but preferred embodiment thereof, shown in the accompanying drawing, throughout the several views of which corresponding reference characters are used to designate corresponding parts, and in which:

Figure 1 is a perspective view, in side elevation, of a wiper assembly embodying the present invention; t

Fig. 2 is a view in vertical section, taken along the line 2 2 of Fig'. 1;

vFig. 3 is a view in vertical section of the wiper element of the present invention, showing the formation thereof prior to the nal trimming operation, and illustrating the trim lines thereof;

Fig. Ll is a View, partly in vertical section, of the improved molding apparatus kof the present invention;

Fig. 5`is a view in elevation, taken on the line 5 5 of Fig. 4, and illustrating the condition of the wiper strip after the initial molding operation;

Fig. 6 is ya diagrammatic view of preferred trimming apparatus; and,

Fig. 7 is a fragmentary view of a wiper element embodyingA side projections.

Referring first to Figs. 1 and 2, the Wiper strip designated generally as I0 comprises an elongated strip of relatively flexible material, such as rubber or its equivalent, the wiping edge I2 of y which is accurately formed as a straight edge and thus adapted to have continuous contact with la correspondingly straight windshield or other area to be cleaned. In accordance with conventional practice, strip I0 may be suitably secured within a4 backing member or channel I4, which in turn may be suitably pivotally connected to an arm I6 associated with suitable actuating mechanism for the wiper. The details of the channel I4 and of the connection thereof toarm I6 form no part of the present invention and so are not illustrated or described in detail. It will be understoodthat in usual operation, the arm I8 is suitably reciprocated or oscillated to correspondingly reciprocate or oscillate the strip lil back and forth across the windshield or other area to ybe cleaned and that incertain instances the channel I4 may be loosely connected to the arm I6 to permit a certain amount of opping thereof to supplement the flopping action due to the flexibility of strip III, as hereinafter discussed in more detail.

In the illustrated,construction, strip `I 0 is formed of a relatively thin wiping portion I8 and a Wider backing portion 20, which portions merge in sloping shoulders 22. Imbedded Within the wiping portion I8 and extending in the illustrated construction somewhat into the backing portion 20, A

but falling slightly short of the lower edges of the channel I4, is a stiifening member 24. The member 24 is preferably formed of a spring-like metallic strip, for instance steel, brass or the like, although any vvmaterial 'having the desired char- "however, serves to permit-some deformation in use of the edge l2 from a straight line-thereby enabling the strip to follow irregularities of the glass or other surface. Preferably, the stiffening f element 24 is vulcanized or otherwise positively f bonded to the strip l0, such' bonding beingfcon- `v4`formed in the mold members.

Figs. l and 5, a plurality of pairs of the plungers are llocated along the mold in generally spaced relation. l

tinuou's over the surface of the element 24 to thereby prevent working or movement of the element vwithin the strip.

It-will be understood that in practice,- varying operating conditions will require the use of differing grades of rubber, differing materials for the stiffening elements, and differing dimensions for these parts. It has been found, however, that an effective and satisfactory construction is proy formv the element 24 of an initial length somevided by using a relatively flexible rubberof cornmercial grade for the strip and spring steel for the stiffening element. ln certain instances, it

v has been found satisfactory to vulcanize the rubber directly to the steel and in certain other yin- I 'stances it is found desirable to first plate'the stiffening element where made of steel with brass or other metal having good bonding character- K istics. Illustrative dimensions for the strip and lfor the stiiening element are those given below:

.j Thickness of portion i8 ofstrip lil-from .020

to .040" Thickness of backing portion 20 from .050 -to .080

` Width of portion IS-'f Distance marginal edge l2 projects beyond element 24-%" Distance strip l0 projects from channel l41/4" Thickness of element 24--.004".010"v In the operation of the illustrated embodiment, the strip l0 may be expected to assume substantially the position shown in dotted lines in Fig. 2

relative tothe channel i4, assuming movement of the latter to the right as viewed in Fig. 2f; and assuming further that channel i4 remains normal to the supporting surface duringsuch movement. In case tilting of channel i4 occurs, it ywill 28 thereof, the trailing marginal edge i being l' spaced away from the surface. It will be evident that even though edges 28 and 30 may dull somewhat in use, the resulting engaging worn surface will be relativelyv narrow since the entire thickness of portion lil is of very small value.

Referring to Figs. 3 through 6, apparatus is illustrated for practicing a preferred method of manufacturing the strip i0 described above. In Fig. 4 a pair of mold members 32 and 34 having opposed and similar cavities 36 and 33, are provided and may be separated and brought into' molding relation with each other in any desired or usual way. Proper spacingof. the stiiening 0i strip it- During reverse movement,

' low for this trim material.

use of a pluralityof pairs of plungers 40 and 42, which are secured in recesses provided therefor in the mold members 32 and 34,*respectively, and

i which are provided on their inner ends with reduced sections 44 and 46, respectively. Their relation is such that when the mold members 32 and 34 are brought into the position shown in Figure 4, the spacing between `the projections 44 element 24, `so that it will be equidistant from f the opposing faces of the strip i0, is insured by and 46 `is ljust suicient to accommodate the stiiening` element 24. The plungers are located in this position through the engagementv of the outer ends thereof with shoulders 48 and 50 As best seen 'in It will be evident that the plungers 4t and 42 fect a preliminary positioning, it is preferred to what greater than that of the mold, so that the ends 24a and 24h project therebeyond and may begrasped either manually or by'suitable clamps, ormay be received in locating grooves in one or both of the mold sections; tolocate the strips in accurate relation relative tothe molds. Once the molds are brought together, plungers 40' and 42 act both to' space strip 24 equidistantly from the mold faces and also to space the edge 26 of element 24v in parallel relation to the wiping edge of the strip. A i

kIn the use of the mold, it will be understood that withzthe mold sections 32`and 34 in separated relation, a'stiifening` element `24 is properly positioned relative to one of the mold sections in the kmanner just stated, anda gob'of rubber or other kcompound is placed in one ofthe cavities 36 and 38 and preferably distributed along the length thereof; Thereafter, the two mold sections are brought together, as anincident to which the plungers 40 and 42 act rto properly support ele-- nient 24 and in the course of which the rubber orv other compound is forced into the form shown .invFig 4. This molding process may be effected under. both heat and pressure and results both in molding the rubber to the completed shape-J shown in Fig. 3l and in vulcanizing the strip to thek element 24, the bond being continuous, las

previously stated, over the entire surface of the element 24. Ends 24a; and 24h may be trimmed ofi` after the molding operation in any usual manner.'

The final manufacturing step preferably includes a trimming operation in which the upper edge Illa. and the lower edge lflb are trimmed away, the mold dimensions being such asto a1- V A preferred cutting off mechanism may include, as shown in Fig. 6, a pair of externally driven cutter wheels 50 and 52, the relatively thin blades 54 and 56 of which travel in closely adjacent relation to the sides'v posed to have the backV thereof trimmed and the other being disposed to; have the lwiping edge thereof trimmed. 'I he cutter wheels 5D and 52 and the vise structure 62 may be reciprocated relative to reach other in any suitable way, vise structure $2 being illustrated as slidably supported upon ways 1G. The cutter wheels 5 and 52 are preferable operated at relatively high speeds and, the strip I@ being firmly supported' within the vise structure 62, the resulting inarginal edges formed by the cutter wheels are very straight. In practice, the supplementing of the molding process by a cutting or trimming operation is found to produce blades of substantially improved quality.

Referring now to the embodiment of the present invention shown in Fig. 7, the Wiper element IQ is constructed in general as described above, being provided with the wiping portion I8', the shouldered backing portion 20', and the stiffening element 24', all of which may and preferably are related to each other in the previously described manner. A projection 8O is formed at each side of the wiping portion I8, adjacent but in spaced relation to the wiping edge I2 thereof, which projections are of tapered formation and terminate in edges 82. The lower surface of each projection 82 may be plane but it is preferred to form the upper surface thereof arcuately.

In operation, the wiper element Illa may be expected to assume substantially the position shownin dotted lines in Fig. '7, for the reasons described more particularly with reference to the preceding figures. In such deflected or trailing position, the leading edge 28 engages the glass or other surface to be cleaned in the previously described manner. The deflection also brings edge 82 o-f the leading projection 80 into engagement with the glass or other surface to be cleaned, so that the wiper thus engages such surface along two lines, one afforded by edge 28' and the other by edge 82.

The projections may be relatively lightin weight since they extend only short distances from either face of the element I0', and receive support from the stiffening element 24.

It will be noted that the arcuately formed face of the leading projection 82 meets the glass or other surface in advance thereof at an interior angle which exceeds degrees, so that inA operation, the edge 82 acts as a shovel to lift or scale foreign matter from the glass. This shoveling action occurs prior to the passage over the glass of the previously described wiping edge I2' and effects a preliminary cleaning which is completed by the latter wiping edge.

In practice, since the cleaning action afforded by the projections may be regarded as preliminary, it is found to be practical to form the wiping edges 82 by molding, and thus to dispense with the necessity of cutting or machining such edge. The assembly may be characterized, therefore, as combining the -economy of a molding operation in forming the projections 80 with the improved operation of a cut edgein forming the wiping edgelZ.

It is thought to be evident that the wiper element illustrated in Fig. 7 may be formed by molding apparatus corresponding in all respects to that described with reference to Figs. 3 through 6, the `only difference involved being a. suitable modification inthe shapes of the lmold cavities.

It is, therefore, considered unnecessary todescribe the molding apparatus in greater detail.

Although specific embodiments of the present invention have been described, as well as specic methods of and apparatus for manufacturing the same, it will be evident that the invention is susceptibl-e of practice in forms other than the deand having a stiffening strip of resilient material embedded therein and disposed to flex therewith, said stiffening strip extending in proximity to but in spaced relation to said wiping edge, said spaced distance being insuiiicient to permit substantial flexing of said wiping edge independent.'

of said stiffening element but sufficient to permit said wiping edge to accommodate itself to irregularities of a surface being wiped.

2. A wiping element comprising a shouldered strip of resilient material, having an enlarged' back portion and a relatively thin wiping portion provided with a wiping edge, and a strip of stiffening material embedded in said strip extending from a point in proximity to but spaced from said wiping edge into said enlarged portion, said spaced distance being insufcient to permitv substantial flexing of said wiping edge independent of said stiffening element but sufficient to permit said wiping edge to accommodate itself to irregularities of a surface being wiped. Y

3. A vwiper assembly, comprising in combination a backing member; a wiper strip ofv shouldered formation having a relatively thin wiping portion and an enlarged backing portion, said backing portion being secured within said back-l ing member but having a part projelting therefrom, said wiping portion being provided with a wiping edge; and a stiffening element embedded within said strip and extending from a point in proximity to but spaced from said wiping edge to a point within said projecting part, vsaid spaced distance being insuhcient to permit substantial flexing of said wiping edge independent of said stiffening element but sufficient to permit said wiping edge to accommodate itself to irregulari- I 5. A working element formed of resilient material and having a plurality of spaced resilient wiping members with wiping edges disposed to engage a surface to be cleaned in succession, certain of said edges being so formed that the leading face thereof meets such surface at an interior I angle in excess of 90 'degrees and certain others thereof 4meeting such surface at an angle less than 90 degrees.

' VICTOR I-I. CHRISTEN. 

